To stay competitive, the companies have to respond quickly to the changing demands of customers. At the same time, the products become more and more complex, including more complex functionalities, and enterprises now have to deal with concurrent multi-disciplinary environments if they want to optimize their products globally. This would come with the development of in-process simulations, but new methods and new tools are needed in order to enable a bridge between the development domains. An important approach is Digital Mock-up (DMU), which provides a robust development method to enable the spatial integration in concurrent environment. In the past decade the DMU has been implemented as a mandatory development method ensuring good project progress within distributed collaborative development. Nevertheless, there is a strong need to pursue the product development by additional methods, which progress beyond DMU. The development of mechatronic systems involves many disciplines, which utilize their own specific methods, processes as well as software tools in order to create partial models of an overall system. A very tight collaboration of the disciplines is essential, since all the partial models are interdependent. However, information between these engineering domains is exchanged only periodically. Progressing rapidly in short steps, the developers need an assisting tool to vividly obtain the first impression on functional behavior of their products (“physicalisation of data”) in each stage of product development. This paper describes a new approach of cross-skill engineering cooperation between various engineering domains (mechanical, electrical, software etc.) called Functional DMU which provides a first, quick insight (functional spatial experience) in the recent progress of singular development tasks and corresponding results in the context of the whole product.